In some storage arrangements, clusters of storage controllers can be provided to improve performance, provide redundancy, and provide load balancing. Requests received from client computers are processed by the storage controllers. The storage controllers send access commands to respective storage subsystems to perform actions (e.g., reads, writes, deletes, etc.) specified by the requests from the client computers.
Storage volumes, which are logical units of data, can be defined in the storage subsystems that are controlled by the storage controllers. Under certain conditions, such as in the presence of failures or other faults, performance of the cluster of storage controllers may be degraded.